Systems have been developed to augment a human surgeon's ability to perform surgery on a patient by providing the surgeon with intraoperative images of anatomical structures within the patient's body. Typically, these systems comprise a specialized form of camera or medical telescope. Further, a class of these systems, which includes endoscopic and laparoscopic instruments, has reduced the invasive nature of many surgical procedures.
This class of systems has two salient characteristics in common: First, the surgeon using the system cannot directly manipulate the patient's anatomy with his fingers, and second, the surgeon cannot directly observe what he is doing. Instead, the surgeon must rely on instruments that can be inserted through a trocar or through a working channel of an endoscope. Often, since his hands and attention are fully occupied in performing the procedure, the surgeon must rely on an assistant to point the endoscopic camera while the surgery is performed.
To ameliorate the awkwardness of this arrangement, robotic augmentation devices have been developed for endoscopic surgery. One such device is described in detail in a U.S. patent application entitled “System and Method for Augmentation of Surgery” Ser. No. 07/714,816 filed Jun. 13, 1991 which is herein incorporated by reference.
Robotic augmentation devices can potentially greatly assist surgeons during an operation. Robotic devices do not fatigue. Potentially, they can position medical telescopes and surgical instruments very accurately and can perform precise repositioning and repetitive functions. However, in order for these advantages to be realized, a number of problems need to be solved. The surgeon still needs to determine what motions the robotic device is to make and requires a means to communicate with the computer controlling the robot. In a few cases, such as orthopaedic machining of bone or preplanned excision of a tissue volume determined from preoperative medical images (such as CT or MRI scans), these motions may be preplanned. However, in other cases, the surgeon needs to directly observe the patient's anatomy and interactively specify the motions to be made relative to anatomical features and the medical telescopes. In these cases, means of accurately locating anatomical features and instruments relative to the medical telescopes and to each other and of using this information to control the robotic augmentation aids are necessary.
A specialized robotic device for stepping a resectoscope through a preprogrammed sequence of cuts in thranurethral prostatectomies has been developed. However, this system does not address the problem of providing the surgeon with a convenient means of controlling the view available through an endoscopic device or of providing the surgeon with means of interactively manipulating surgical instruments in response to intraoperative imaging and other sensory information.
There has been one attempt to provide voice control of a flexible endoscope in which servomotors attached directly to the control knobs of a commercial flexible endoscope were activated in response to voice commands by the surgeon. Difficulties of this approach include: (a) the surgeon (or an assistant) must still determine which direction to deflect the endoscope tip to provide a desired view and, consequently, must keep track of the relationship between the endoscope tip and the anatomical structures being observed; (b) these corrections must be made continually, distracting the surgeon from more important matters; and (c) the use of voice commands for this purpose is subject to errors, potentially distracting to the surgeon, and may make the use of voice for communication between the surgeon and operating room personnel more difficult.
Several research efforts are directed to providing improved mechanisms for flexible endoscopes. These devices do not, however, simplify the surgeon's problem of controlling the endoscopic camera to obtain a desired view, either by himself or by communicating with a skilled operator.